If you are a third party developer for Twitter, you used to receive the benefit of appearing in a link below tweets that are sent by users of your service. This negatively affects companies like Hootsuite, Tweetbot, Ecofon, etc. Now when browsing Twitter.com, you will not see how each tweet was posted any more. This change has already been reflected in the Twitter mobile app. People that hate the Twitter API restrictions have started a popular hashtag called #OccupyTwitter.